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ToolsCompareSemax vs Thymosin Alpha-1

Semax vs Thymosin Alpha-1

Side-by-side comparison of key properties, dosing, and research.

Cognitive Enhancement
Semax
Immune SupportAnti-Aging & Longevity
Thymosin Alpha-1
Summary
Semax is a synthetic heptapeptide derived from ACTH developed in Russia. It is a potent nootropic that enhances memory, focus, and provides neuroprotection. Approved in Russia for cognitive disorders, stroke recovery, and traumatic brain injury.
Thymosin Alpha-1 is a naturally occurring 28-amino acid peptide derived from the thymus gland. It is a powerful immune modulator approved in many countries for treating chronic hepatitis B, hepatitis C, and as an adjunct in cancer immunotherapy.
Half-Life
Minutes (but effects persist for hours via BDNF induction)
2–3 hours
Admin Route
Intranasal, SubQ
SubQ
Research
Typical Dose
0.25–1 mg (250–1000 mcg)
0.8–1.6 mg
Frequency
1–2 times daily
Twice weekly
Key Benefits
  • Enhances memory and learning
  • Improves focus and concentration
  • Increases mental energy and motivation
  • Provides neuroprotection via BDNF and NGF upregulation
  • Reduces cognitive decline
  • May alleviate ADHD symptoms
  • Supports recovery from brain injury and stroke
  • Fast-acting — effects within 30–60 minutes
  • Approved in Russia for cognitive disorders and stroke recovery
  • Enhances T-cell and NK cell activity
  • Supports recovery from viral and bacterial infections
  • May reduce inflammation systemically
  • Supports healthy aging and immune resilience
  • Improves vaccine response
  • Supports liver health
  • May help with chronic fatigue syndrome and post-viral conditions
  • Approved in multiple countries for hepatitis B and C treatment
Side Effects
  • Headache (rare, often from higher doses)
  • Anxiety or overstimulation at high doses
  • Sleep disruption if dosed too late
  • Irritability (uncommon)
  • Injection site irritation
  • Mild flu-like symptoms initially (immune activation)
  • Fatigue (rare)
Stacks With